1 files changed, 6 insertions, 0 deletions
diff --git a/src/test/ui/box/alloc-unstable-fail.rs b/src/test/ui/box/alloc-unstable-fail.rs
new file mode 100644
index 000000000..942757164
--- /dev/null
+++ b/src/test/ui/box/alloc-unstable-fail.rs
@@ -0,0 +1,6 @@
+use std::boxed::Box;
+
+fn main() {
+    let _boxed: Box<u32, _> = Box::new(10);
+    //~^ ERROR use of unstable library feature 'allocator_api'
+}